Which process results in the largest change in temperature, adding a certain amount of heat at constant pressure, constant volume, or constant pressure?

2.

Try adding a certain amount of heat at constant temperature to move the system from an initial state 1 to a final state 2. Now, returning to the same initial state, remove heat at constant volume until you arrive at the pressure of state 2, and then add heat at constant pressure until you bring the system to state 2. For the two different paths to get from state 1 to state 2, what is the same and what is different?

3.

For a closed cycle, where the system returns to its original state, when is the net work done by the system positive and when is it negative?